The present invention relates to a tab lifting tool suitable for use on radiators of a type commonly used to cool motor vehicle engine cooling water.
Motor vehicle radiators are commonly made up of a core block consisting of several adjacent thin walled heat conductive tubes extending between top and bottom plastic tanks. Extending around either end of the core block are plates which form part of the core block. These plates have tabs formed around their periphery which are crimped over a flange of a corresponding tank to hold the flange in sealing engagement with a gasket located between the plate and the flange.
Ordinarily, to repair such a radiator it is necessary to first remove the tanks in order to obtain access to the tube ends. Most often implements such as screwdrivers are used to raise the crimped tabs. Such an operation not only often leads to damage of the tanks and/or tabs but is extremely time consuming and tedious. Consequently, it has become commonplace to discard damaged radiators rather than attempting to repair them.
A machine for raising such tabs is disclosed in U.K. patent application GB No. 2,035,168 A, invented by Lawrence Potter and published June 18, 1980. The Potter device has a pair of sturdy elongated jaws or workholders running the length of a tank for gripping the radiator on each side below the tank. A pneumatically operated clamp acts on the top of the tank to constrain the radiator against vertical movement and hold it against the work holders compressing the gasket. A tool with a blade like tip mounted on a slide and moved longitudinally by a motor operated, threaded lead screw engages each tab successively and bends it back to an upright position. Aside from being large, complex and relatively expensive, the Potter machine can not easily lift tabs around the curved ends of the tank. Moreover, with obstructions such as hose connections it is necessary to pivot the tool holder away to clear such obstructions. Finally, the Potter device only lifts tabs; it does not crimp them as well.
U.S. Pat. No. 3,180,128 issued Apr. 27, 1965 to Faulkner discloses a crimping tool having an elongated actuating member slidable in the barrel of the tool and actuated by a pivotally mounted trigger coupled to the actuating member at one end. The Faulkner device is designed to crimp the edges of a panel for an automobile or the like and not for lifting or crimping tabs. Moreover, the Faulkner device is capable only of crimping tabs and would not be adaptable to repairing such items as a radiator, the repair of which generally depends on both lifting and crimping the tabs over a flange.
U.S. Pat. No. 3,742,571 issued July 3, 1973 to Brehm discloses a tool for trimming the ends of wires and inserting them into the terminals of a multi-contact electrical connector. The device includes a reciprocal ram operated by a pivotally mounted trigger, the ram being biased toward a retracted position. An upwardly extending arm contacts one side of the connector while the ram forces the wire into the connector on the other side in response to manual pivotting of the trigger. As in Faulkner, Brehm is not a tool which is adapted to crimping or lifting tabs even though it does disclose the general concept of bracing a tool casing against one side of a work base and forcing a slidable member within the casing against another side of the work base. Since most repair operations involve both lifting and crimping, the known tools are not sufficient to be utilized for the latter purpose.